## Inheritance Semantics:
Decorators:
1) list the decorators of the class and its parents in the ancestor first order
2) only use the last decorator of each kind (e.g. @Component / ...)
Constructor parameters:
If a class inherits from a parent class and does not declare
a constructor, it inherits the parent class constructor,
and with it the parameter metadata of that parent class.
Lifecycle hooks:
Follow the normal class inheritance model,
i.e. lifecycle hooks of parent classes will be called
even if the method is not overwritten in the child class.
## Example
E.g. the following is a valid use of inheritance and it will
also inherit all metadata:
```
@Directive({selector: 'someDir'})
class ParentDirective {
constructor(someDep: SomeDep) {}
ngOnInit() {}
}
class ChildDirective extends ParentDirective {}
```
Closes#11606Closes#12892
Every decorator now is made of the following:
- a function that can be used
as a decorator or as a constructor. This function
also can be used for `instanceof` checks.
- a type for this function (callable and newable)
- a type that describes the shape of the data
that the user needs to pass to the decorator
as well as the instance of the metadata
The docs for decorators live at the followig places
so that IDEs can discover them correctly:
- General description of the decorator is placed on the
`...Decorator` interface on the callable function
definition
- Property descriptions are placed on the interface
that describes the metadata produces by the decorator
Closes#9729
BREAKING CHANGE:
`Type` is now `Type<T>` which means that in most cases you have to
use `Type<any>` in place of `Type`.
We don't expect that any user applications use the `Type` type.
Mostly, removing things that were never intended to be exported publicy.
BREAKING CHANGE:
The following are no longer publicly exported APIs. They were intended as internal
utilities and you should use your own util:
```
browserDetection,
dispatchEvent,
el,
normalizeCSS,
stringifyElement,
expect (and custom matchers for Jasmine)
```
This lets users continue using runtime-sideeffect Decorators if they choose,
only down-leveling the marked ones to Annotations.
Also remove the "skipTemplateCodegen" option, which is no longer needed
since Angular compiles with tsc-wrapped rather than ngc. The former doesn't
include any codegen.
Tobias Bosch
Victor Berchet
Alex Eagle
Joao Dias
Miško Hevery
Jason Choi
Marc Laval
Julie Ralph
ScottSWu
Alex Eagle
ScottSWu
Igor Minar